From the US Department of Justice press statement regarding the indictment of two US citizens for involvement in a failed coup in The Gambia --
Prior to departing for The Gambia, between August and October 2014, Faal and other co-conspirators purchased multiple firearms, including M4 semi-automatic rifles, and shipped them to The Gambia for use in the coup attempt. Members of the conspiracy also acquired night-vision goggles, body armor, ammunition, black military style uniform pants, boots, and other personal equipment.
All these purchases appear to have been legal.
Prior to departing for The Gambia, between August and October 2014, Faal and other co-conspirators purchased multiple firearms, including M4 semi-automatic rifles, and shipped them to The Gambia for use in the coup attempt. Members of the conspiracy also acquired night-vision goggles, body armor, ammunition, black military style uniform pants, boots, and other personal equipment.
All these purchases appear to have been legal.